feat(bootstrap): refactor runtime dependency management and add lazy loading for binary store and vector index

feat(agent): update import for agent session service
feat(openai): add context truncation check in OpenAI answer generator
docs(README): update frontend environment file conventions
fix(vite): default local frontend development to local backend

frontend/.env

@@ -0,0 +1,2 @@
+VITE_API_PROXY_TARGET=http://6.86.80.8:8000
+FRONTEND_PORT=5173

frontend/.env.development

@@ -0,0 +1,2 @@
+VITE_API_PROXY_TARGET=http://127.0.0.1:8000
+FRONTEND_PORT=5173

frontend/.env.example

@@ -0,0 +1,2 @@
+VITE_API_PROXY_TARGET=http://127.0.0.1:8000
+FRONTEND_PORT=5173

frontend/README.md

@@ -49,6 +49,12 @@ npm run dev
 
 启动本地开发服务器，默认访问 `http://localhost:5173`
 
+前端环境文件约定如下：
+
+- `frontend/.env.development`：本地开发，默认代理到 `http://127.0.0.1:8000`
+- `frontend/.env.production`：生产构建，默认代理到 `http://6.86.80.8:8000`
+- `frontend/.env.local`：临时覆盖本机配置，优先级高于上面两者
+
 ### 构建生产版本
 
 ```bash

frontend/src/pages/RagChat/CitedAnswer.tsx

@@ -1,4 +1,4 @@
-import React, { useRef } from 'react';
+import React from 'react';
 import { useTheme } from '../../contexts';
 import type { RetrievalData } from '../../types';
 

frontend/vite.config.ts

@@ -4,7 +4,8 @@ import react from '@vitejs/plugin-react'
 // https://vite.dev/config/
 export default defineConfig(({ mode }) => {
   const env = loadEnv(mode, process.cwd(), '')
-  const apiHost = env.API_HOST || '6.86.80.8'
+  // Default local frontend development to the local backend unless explicitly overridden.
+  const apiHost = env.API_HOST || '127.0.0.1'
   const apiPort = env.API_PORT || '8000'
   const proxyTarget = env.VITE_API_PROXY_TARGET || `http://${apiHost}:${apiPort}`